Eu-based metal-organic framework as a multi-responsive fluorescent sensor for efficient detecting Cr2O72− and tetracycline hydrochloride

In this paper, we successfully synthesized a europium-based metal−organic framework {[Eu(TATB)(H2O)]}n (1) under solvothermal condition, where H3TATB ​= ​4,4′,4″-s-triazine- 2,4,6-tribenzoic acid. 1 exhibits excellent water and thermal stability. This ultra-stable material can rapidly detect Cr2O72− and tetracycline hydrochloride (TCH) in aqueous solution with excellent selectivity and sensitivity based on the luminescent quenching with relatively low limits of detection (5.50 ​μM for Cr2O72− and 4.88 ​μM for TCH). Furthermore, the possible mechanisms of fluorescence quenching in the sensing process were systematically studied by PXRD, UV–vis, and electrochemical cyclic voltammetry. In addition, white-light emission is achieved through a reasonable tuning proportion by mixing Eu3+, Tb3+ and Gd3+.